One-Arm Pullup How-To
Hang on a pullup bar with one arm at full extension.
“In the beginning, you might want to swing your off-arm to get some momentum to lift your body for your first rep,” Sandler says. “After that, get your other arm out of the way and do as many as you can. Also, if you want to use a spotter, they can help by giving you a little nudge here and there, so you’ll only get help where you need it and not for the full rep.”
One-armed pullups should go at the beginning of your back day (after warming up, of course) when you’re fresh because—news flash—it will be the hardest thing you do.
As far as sets and reps, Sandler suggests going to failure with each set—even if you can only do one—and taking up to three full minutes between sets.